Thousands of health workers in Northern Ireland including nurses and ambulance staff staged a four-hour strike over pay as unions said the mood for action is "strengthening".
Picket lines were mounted outside hospitals and ambulance headquarters between 8am and midday across the province as unions demand a recommended 1% pay rise to be implemented for all staff. The Unite and GMB members were among thousands of NHS workers who also took part in walkouts across England.
The Government has said it cannot afford the rise without risking front line jobs.
Unions have already agreed a pay rise with the administrations in Scotland and Wales, leaving England and Northern Ireland without the proposed raise.
Kevin McAdam from Unite, however, said members "cannot and will not" sit back and take further cuts to pay.
"The next stage is to continue an eight-week period of working the normal hours to expose the amount of time our members work without getting a penny," he said.
"We think that will expose pressures on the service and we will use that to continue with our campaign with the minister.
"We are not considering further action this side of the new year, but rather than the mood waning the mood is strengthening.
"Our members are not just employees they are users of the service."
The strike action comes amid massive cuts in services - including the temporary closure of minor injury units - set to save millions of pounds.
"When the cuts happen they will take up the slack," Mr McAdam added.
"It can't be expected that their shoulders get broader and broader with the strain. They just can't take it any more."
Ministers in England have awarded NHS staff a 1% increase, but only for those without automatic progression-in-the-job rises.
An independent pay review board had said the increase should be across the board.
Wales implemented the same policy as England but gave extra to the lowest paid.